In order to protect humans against smoke, noxious fumes or contaminated air which may erupt in a variety of building structures, particularly in office buildings, hotels, manufacturing plants, mines, and the like, many different types of shielding devices have been developed over the years which are operative to seal off certain openings through which smoke, noxious fumes or contaminated air are likely to travel. As is well known, many deaths and much property damage are the result of smoke, noxious fumes or air contamination, so there have been various different approaches proposed to rapidly sealing off areas adjacent to which smoke, noxious fumes or contaminated air are likely to travel.
Examples of such prior patented approaches to sealing off certain openings are disclosed in:
U.S. Pat. No. 3,766,958 issued to Mitchell PA1 U.S. Pat. No. 3,960,216 issued to Isobe PA1 U.S. Pat. No. 4,077,474 issued to Hattori PA1 U.S. Pat. No. 4,079,772 issued to Klaenhammer et al. PA1 U.S. Pat. No. 4,398,371 issued to Jenkins
all incorporated herein by reference.
Other prior approaches to sealing off openings for the purpose of isolation of smoke, noxious fumes or dangerous air conditions include horizontally and vertically deployed metal and plastic screens. These latter types of prior art sealing approaches have exhibited many operational disadvantages and have proven ineffective to provide an airtight seal. In addition, maintenance personnel can alter many of these schemes after installation which modifies their effectiveness at a time of emergency. Most if not all of the disadvantages associated with the above patented art as well as the latter prior art sealing approaches have been overcome by the new and useful improvements disclosed and claimed in my co-pending U.S. patent application Ser. No. 07/744,079 filed Aug. 14, 1991 and entitled APPARATUS AND METHOD FOR RAPIDLY AND RELIABLY SEALING OFF CERTAIN EXIT AND ENTRANCE WAYS IN RESPONSE TO SMOKE OR FIRE which is incorporated herein by reference.